Tag Archives: flashing

Synthetic Stucco – Why Weeping Holes Are Important

Posted by Admin on September 5, 2011 None comments

Synthetic Stucco (actually known as EIFS) is a popular cladding among both commercial buildings and residential homes in Northern climates because of it’s superior ability to insulate a wall and manage moisture. The moisture management comes primarily from 2 important components of EIFS:

  1. The weather barrier (typically trowel-applied) that acts as a back-up defense against any incidental moisture that gets past the outer barrier
  2. The drainage cavity created by geometrically defined insulation (read: insulation with grooves in the back) and strategically placed adhesive

There are a number of important details that need to be paid attention to, to ensure the system performs optimally. It’s important to note that the drainage system will work even if the details are screwed up to some degree, just not optimally. What we’ll focus on here is the weeping holes though.

Stucco Weeping Holes

Stucco Weeping Holes on a commercial building

Weeping holes are simply gaps in the caulking that is installed at the base of an EIFS wall. The EIFS can terminate 8″ above grade (per building code requirements), above another material (such as brick or stone) or at the joint between floors. EIFS should be terminated with a flashing that is tied into the weather barrier with the use of an EIFS tape, so that water is diverted away from the wall, out onto the exterior surface. Caulking is then installed between the flashing and the EIFS termination (the underside of the EIFS), with weeping holes every 24″ (or per manufacturer specifications).

The caulking prevents excessive wind-driven rain, and/or insects from entering into the EIF system from the bottom. The weeping holes provide adequate area for air flow and drainage of incidental water, while being small enough to act as a deterrent to insects. There’s actually a study floating around somewhere that concludes that the ventilation within an EIFS wall is enough to create an inhospitable environment for bugs to nest.

The lack of weeping holes when caulking is present is strangely common – whether by fault of the EIFS contractor being improperly trained (or maliciously lazy – is that an oxymoron?), a site supervisor lacking the knowledge, or inadequate inspection from the manufacturer. An EIFS wall without adequate drainage from the bottom may suffer from:

  • Precipitate buildup at the caulking
  • Inadequate air-flow for ventilation

Both of which will generally shorten the life of the EIFS wall itself. Will a general contractor who is on the job to ‘get it done and move onto the next’ care? Not likely. The EIFS wall probably won’t fail within the GC’s liability/warranty period, and they probably have backlash against the installer or supplier of the EIFS system regardless. It’s more about ensuring that EIFS countinue to be seen as a reliable, effective cladding for the sake of the future of the industry.

Oh, and the person who ends up owning or using the building. They’re important too.

The EIFS Lies Countinue

Posted by Admin on December 8, 2009 None comments

Source: http://www.scottshepard.net/remaxil/modules/agent/agent.asp?p=pagecontent.asp&nav=1&pid=42&acc=89890

It’s ironic this guy’s last name is Shepard, because he’s leading his clients astray. Even today, uninformed real estate agents, building inspectors and many others are posting and re-posting false information about EIFS. I just need to address a few of the issues with this article:

1)

In 1994, moisture damage to the interior of walls was being linked to EIFS. In August 1995, 32 EIFS clad homes in North Carolina were tested and 30 were found to have moisture problems. In January 1996, the National Association of Home Builders issued a “Builders Alert” about EIFS. In May 1996, Raleigh North Carolina, imposed a moratorium on the product through January 1997. In March 1996, the North Carolina Building Code Council adopted stringent guidelines for the application of EIFS mandating that a drainage system be installed in the exterior walls of EIFS homes. By September 1996, twelve class-action lawsuits had been launched in the States. In September 1996, Maryland Casualty Company notified its clients, who were contractors, that work with EIFS systems would no longer be insurable. At about the same time, a major relocation company advised its clients that it would eliminate the guarantee on EIFS homes for employees seeking their services during a transfer.

The Mortgage Division of the Chevy Chase Bank decided about the same time to no longer accept mortgages on houses built with Synthetic Stucco. In January 1997, the Georgia Association of Realtors changed its property disclosure statement to disclose whether the house was built with EIFS.

It’s amazing how things can look bad when you stop half way through History. Could you imagine if we only knew about world war 2 up until 1940? I’d be scared for my life that Hitler was in power. That’s exactly what these uninformed “professionals” have done. Further testing revealed that the source of water intrusion was around window penetrations due to poorly specified and installed details. North Carolina later found that this problem was not exclusive by any means to EIFS, but to just about any cladding. Jump forward a few more years, and barrier EIFS (the type where the moisture problems were possibly with – are no longer being recommended by manufacturers, but have been replaced by a new system – dual-barrier/drainage EIFS.

2)

There are many different systems offered by various manufacturers, but in general, EIFS wall systems consist of a wood frame wall (usually 2×4 or 2×6 lumber), covered with sheathing such as plywood, OSB, or gypsum board. Plastic foam insulation boards are then glued or fastened to the sheathing. A 1/16- to 1/4- inch-thick stucco base coat is troweled on to the insulation. A glass fiber reinforcing mesh is imbedded in the base coat. Finally, a finished coat is sprayed, troweled or rolled on. This finish coat provides the color and texture of the home. Many installations have no building paper or housewrap behind the stucco to act as a backup material.

Again, this WAS the situation with EIFS, but isn’t any longer.

3)

Rainwater appears to be getting into the wall systems through imperfections in the stucco. These include joints around windows and doors and penetrations from railings, wiring, plumbing, vents, etc. Once water gets behind the system it gets trapped, leading to mold, mildew and rot of the sheathing, studs, flooring and other framing members. EIFS houses often look good until sections of the wall are removed revealing concealed damage. The damage can even take place within the first few years of the home’s life. As most of the damage has been found in houses in coastal areas, some have suggested that condensation is a problem; however, since the most severe damage seems to show up around wall penetrations, condensation does not appear to be the culprit. The worst damage is often found below and beside windows.

Modern EIFS allow water to drain, not trapping it any more. Penetrations around window should hardly be considered “imperfections” in the stucco as it’s a detail that the original builder should have properly finished, and not specifically related to EIFS.

4)

There is little that can be done on existing systems short of re-siding or paying fanatical attention to keeping the water out. Caulking and flashing maintenance should be a high priority for people with synthetic stucco houses.

In the very newest installations, contractors are using building paper or housewrap behind the insulation to protect the sheathing. In addition, the newest installations are designed with a drainage system behind the insulation to allow any water, which does get in, to drain out. This is not unlike the drainage system found in a brick veneer home. These improvements should work but only if they are well constructed.

The first point is a good one for any cladding – caulking needs to be replaced as required on any home. This typically needs to be done every 5-10 years for optimal performance, and a sure sign is that it’s cracking or peeling off the frame to which it’s attached.

5)

So far we know that areas of high rain fall, and particularly areas with rain accompanied by wind, result in houses with the most damage. Homes, which have no roof, overhang, a very small overhang or many penetrations through the wall systems (i.e. lots of windows and doors) are also at risk. Unfortunately, a visual inspection cannot tell the whole story and until invasive testing becomes standardized and sufficient data becomes available for our area, concealed damage in synthetic stucco houses will remain a question mark.  If you were planning to purchase or sell a home with EIFS that was installed before 1998, we would recommend a full EIFS inspection be performed and included with your closing documents.

Finally, something I can agree with. Any home a high-rain/wind (i.e. coastal) area is most susceptible to damage, EIFS or not. Small roof overhangs and lots of windows do increase the chances of problems in a cladding. Older EIFS installations do need to be inspected, and an EIFS-specific inspector is what is recommended. That’s not to say all new installations are perfect, EIFS is a very technically installation and there are a lot of contractors out there who are looking to make a quick buck, with no regard to their client or the industry they’re damaging.

Who’s Tim Oglesby? Supposedly “educated professional”: http://activerain.com/homecheck

Window Lacking Flashing and Caulking

Posted by Admin on November 25, 2008 1 comments

Whoever installed the stucco around this window deserves to be sued. There are 3 things I immediately see wrong with this:

Window in EIFS Lacking Flashing and Caulking
  1. There is no flashing over the window, this means that any water in behind the system (which likely isn’t drainage either) will become trapped in and around the window frame, causing mold and rot.
  2. There is no backer rod and caulking around the sides of the window. Aside from water getting into the window frame from the top, it can also be wind-driven into the sides.
  3. The applicators didn’t protect the window properly when applying the finish coat. Now you have an acrylic material caked on to your window frame, and scraping it off will likely damage the finish on the frame.

I have no idea what that white spot is at the bottom of the picture either.

Additional Components of the Weather Barrier

Posted by JamesCarnegie on November 5, 2008 None comments

An EIFS weather barrier is the same as putting building paper around your house, isn’t it? You can just slap it on and you’re safe, right? Yes… and no. Yes, it is a weather barrier which will keep moisture away from your substrate. No, it’s not the only component of a well constructed weather barrier. EIFS has gone through the fire of criticism and condemnation, and come out the other side stronger than any other cladding. It has undergone so much research and testing that it is now correcting faulty building methods in all other sidings as well as professionals’ understanding of their homes. A full weather barrier incorporates not only the weather barrier itself, but also caulking, flashing and window-tie ins in their respective location to keep water at bay.

Around any penetration in EIFS which may move (eg. hose bib, wiring, electrical meters) or openings which may expand and contract at different rates (eg. windows and doors) you will need caulking and a backer rod. Dissimilar materials expand and contract at different rates, causing rigid materials between them (such as a basecoat) to crack and leak water inside. Low-modulus caulking will expand and contract significantly before tearing, making it an ideal material for these gaps. However, caulking will only properly move when adhered to only 2 surfaces, therefore a closed-cell backer rod is required between the gap to provide a third surface, to which the caulking will not stick. It is recommended to caulk between the EIFS and other surface before applying the finish coat, as the caulking will not properly  stick to finish coat.

Low Modulus Sealant Adhered to 2 Surfaces and Backer Rod

Low Modulus Sealant Adhered to 2 Surfaces and Backer Rod

Look around at homes in your neighbourhood next time you’re out — how many windows have flashing over them? Water running behind claddings, then into the window frame is one of the most common causes of moisture problems in homes. Installing “kick out” flashing over a window will “kick out” any intruding water before it enters the window frame, preventing it from traveling any further down the substrate. Flashing needs to be installed starting behind the weather barrier, extending beyond the window frame, with a minimum 3/8″ drip edge (+ return) and sealant on the underside. It’s a good idea to get a color close to your stucco wall or trim (you likely won’t match it exactly) to blend in and minimize any aesthetic disturbance.

An additional step recommended by EIFS manufacturers (though rarely installed by applicators without proding) is window tie-ins using EIFS tape. EIFS tape covers from the outside weather barrier, across the window opening/framing and into the interior to completely seal the substrate, window frame and interior drywall from water intrusion. It is usually supplied as a peel-and-stick membrane (like duct tape), minimizing the time it takes to install and lower the chances of improperly installing it. It is worth asking who will do this as it is not normally within a stucco contractor’s scope of work.

Traditionally, it was uncommon to see flashing and window tie-ins on homes, and caulking (and the previous two) were never done by the EIFS applicator. More and more however, the burden is being placed on stucco applicators to completely seal the wall. Nobody likes asking for their cheque, then being told they’re expected to do more work that wasn’t included in their original scope and pricing. It’s perfectly reasonable to expect the applicators to take care of this step as part of their work — as long as it is clarified in advance so that they can include it in their price.